Speaking indicator for group calls

Co-authored-by: Peter Thatcher <peter@signal.org>
Co-authored-by: Jim Gustafson <jim@signal.org>
Co-authored-by: Josh Perez <60019601+josh-signal@users.noreply.github.com>

ts/components/CallManager.stories.tsx

@@ -1,4 +1,4 @@
-// Copyright 2020-2021 Signal Messenger, LLC
+// Copyright 2020-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import * as React from 'react';
@@ -144,6 +144,7 @@ story.add('Ongoing Group Call', () => (
         groupMembers: [],
         peekedParticipants: [],
         remoteParticipants: [],
+        speakingDemuxIds: new Set<number>(),
       },
     })}
   />
@@ -218,6 +219,7 @@ story.add('Group call - Safety Number Changed', () => (
         groupMembers: [],
         peekedParticipants: [],
         remoteParticipants: [],
+        speakingDemuxIds: new Set<number>(),
       },
     })}
   />

ts/components/CallManager.tsx

@@ -1,4 +1,4 @@
-// Copyright 2020-2021 Signal Messenger, LLC
+// Copyright 2020-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import React, { useCallback, useEffect } from 'react';

ts/components/CallScreen.stories.tsx

@@ -1,4 +1,4 @@
-// Copyright 2020-2021 Signal Messenger, LLC
+// Copyright 2020-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import * as React from 'react';
@@ -103,6 +103,7 @@ const createActiveGroupCallProp = (overrideProps: GroupCallOverrideProps) => ({
   peekedParticipants:
     overrideProps.peekedParticipants || overrideProps.remoteParticipants || [],
   remoteParticipants: overrideProps.remoteParticipants || [],
+  speakingDemuxIds: new Set<number>(),
 });
 
 const createActiveCallProp = (

ts/components/CallScreen.tsx

@@ -1,4 +1,4 @@
-// Copyright 2020-2021 Signal Messenger, LLC
+// Copyright 2020-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import type { ReactNode } from 'react';
@@ -299,6 +299,7 @@ export const CallScreen: React.FC<PropsType> = ({
           isInSpeakerView={isInSpeakerView}
           remoteParticipants={activeCall.remoteParticipants}
           setGroupCallVideoRequest={setGroupCallVideoRequest}
+          speakingDemuxIds={activeCall.speakingDemuxIds}
         />
       );
       break;

ts/components/CallingAudioIndicator.tsx

@@ -0,0 +1,30 @@
+// Copyright 2022 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import type { ReactElement } from 'react';
+import React from 'react';
+import animationData from '../../images/lottie-animations/CallingSpeakingIndicator.json';
+import { Lottie } from './Lottie';
+
+export function CallingAudioIndicator({
+  hasRemoteAudio,
+  isSpeaking,
+}: Readonly<{
+  hasRemoteAudio: boolean;
+  isSpeaking: boolean;
+}>): ReactElement {
+  if (!hasRemoteAudio) {
+    return (
+      <div className="CallingAudioIndicator CallingAudioIndicator--muted" />
+    );
+  }
+
+  if (isSpeaking) {
+    return (
+      <Lottie animationData={animationData} className="CallingAudioIndicator" />
+    );
+  }
+
+  // Render an empty spacer so that names don't move around.
+  return <div className="CallingAudioIndicator" />;
+}

ts/components/CallingPip.stories.tsx

@@ -1,4 +1,4 @@
-// Copyright 2020-2021 Signal Messenger, LLC
+// Copyright 2020-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import * as React from 'react';
@@ -119,6 +119,7 @@ story.add('Group Call', () => {
       deviceCount: 0,
       peekedParticipants: [],
       remoteParticipants: [],
+      speakingDemuxIds: new Set<number>(),
     },
   });
   return <CallingPip {...props} />;

ts/components/CallingPip.tsx

@@ -1,4 +1,4 @@
-// Copyright 2020-2021 Signal Messenger, LLC
+// Copyright 2020-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import React from 'react';

ts/components/CallingPipRemoteVideo.tsx

@@ -1,4 +1,4 @@
-// Copyright 2020-2021 Signal Messenger, LLC
+// Copyright 2020-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import React, { useMemo, useEffect } from 'react';

ts/components/GroupCallOverflowArea.stories.tsx

@@ -1,4 +1,4 @@
-// Copyright 2021 Signal Messenger, LLC
+// Copyright 2021-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import type { FC } from 'react';
@@ -39,6 +39,7 @@ const defaultProps = {
   getGroupCallVideoFrameSource: fakeGetGroupCallVideoFrameSource,
   i18n,
   onParticipantVisibilityChanged: action('onParticipantVisibilityChanged'),
+  speakingDemuxIds: new Set<number>(),
 };
 
 // This component is usually rendered on a call screen.

ts/components/GroupCallOverflowArea.tsx

@@ -1,4 +1,4 @@
-// Copyright 2021 Signal Messenger, LLC
+// Copyright 2021-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import type { FC, ReactElement } from 'react';
@@ -24,6 +24,7 @@ type PropsType = {
     isVisible: boolean
   ) => unknown;
   overflowedParticipants: ReadonlyArray<GroupCallRemoteParticipantType>;
+  speakingDemuxIds: Set<number>;
 };
 
 export const GroupCallOverflowArea: FC<PropsType> = ({
@@ -32,6 +33,7 @@ export const GroupCallOverflowArea: FC<PropsType> = ({
   i18n,
   onParticipantVisibilityChanged,
   overflowedParticipants,
+  speakingDemuxIds,
 }) => {
   const overflowRef = useRef<HTMLDivElement | null>(null);
   const [overflowScrollTop, setOverflowScrollTop] = useState(0);
@@ -114,6 +116,7 @@ export const GroupCallOverflowArea: FC<PropsType> = ({
             getFrameBuffer={getFrameBuffer}
             getGroupCallVideoFrameSource={getGroupCallVideoFrameSource}
             i18n={i18n}
+            isSpeaking={speakingDemuxIds.has(remoteParticipant.demuxId)}
             onVisibilityChanged={onParticipantVisibilityChanged}
             width={OVERFLOW_PARTICIPANT_WIDTH}
             height={Math.floor(

ts/components/GroupCallRemoteParticipant.stories.tsx

@@ -1,4 +1,4 @@
-// Copyright 2020-2021 Signal Messenger, LLC
+// Copyright 2020-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import * as React from 'react';
@@ -36,6 +36,7 @@ const createProps = (
   // eslint-disable-next-line @typescript-eslint/no-explicit-any
   getGroupCallVideoFrameSource: noop as any,
   i18n,
+  isSpeaking: false,
   remoteParticipant: {
     demuxId: 123,
     hasRemoteAudio: false,
@@ -51,6 +52,7 @@ const createProps = (
     }),
   },
   ...overrideProps,
+  ...(overrideProps.isInPip ? {} : { isSpeaking: false }),
 });
 
 const story = storiesOf('Components/GroupCallRemoteParticipant', module);

ts/components/GroupCallRemoteParticipant.tsx

@@ -1,4 +1,4 @@
-// Copyright 2020-2021 Signal Messenger, LLC
+// Copyright 2020-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import type { CSSProperties } from 'react';
@@ -16,6 +16,7 @@ import type { GroupCallRemoteParticipantType } from '../types/Calling';
 import type { LocalizerType } from '../types/Util';
 import { AvatarColors } from '../types/Colors';
 import { CallBackgroundBlur } from './CallBackgroundBlur';
+import { CallingAudioIndicator } from './CallingAudioIndicator';
 import { Avatar, AvatarSize } from './Avatar';
 import { ConfirmationDialog } from './ConfirmationDialog';
 import { Intl } from './Intl';
@@ -41,6 +42,7 @@ type InPipPropsType = {
 type InOverflowAreaPropsType = {
   height: number;
   isInPip?: false;
+  isSpeaking: boolean;
   width: number;
 };
 
@@ -282,6 +284,10 @@ export const GroupCallRemoteParticipant: React.FC<PropsType> = React.memo(
                 module="module-ongoing-call__group-call-remote-participant__info__contact-name"
                 title={title}
               />
+              <CallingAudioIndicator
+                hasRemoteAudio={hasRemoteAudio}
+                isSpeaking={props.isSpeaking}
+              />
             </div>
           )}
           {wantsToShowVideo && (

ts/components/GroupCallRemoteParticipants.tsx

@@ -1,4 +1,4 @@
-// Copyright 2020-2021 Signal Messenger, LLC
+// Copyright 2020-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import React, { useCallback, useState, useMemo, useEffect } from 'react';
@@ -48,6 +48,7 @@ type PropsType = {
   isInSpeakerView: boolean;
   remoteParticipants: ReadonlyArray<GroupCallRemoteParticipantType>;
   setGroupCallVideoRequest: (_: Array<GroupCallVideoRequest>) => void;
+  speakingDemuxIds: Set<number>;
 };
 
 enum VideoRequestMode {
@@ -85,6 +86,7 @@ export const GroupCallRemoteParticipants: React.FC<PropsType> = ({
   isInSpeakerView,
   remoteParticipants,
   setGroupCallVideoRequest,
+  speakingDemuxIds,
 }) => {
   const [containerDimensions, setContainerDimensions] = useState<Dimensions>({
     width: 0,
@@ -266,8 +268,12 @@ export const GroupCallRemoteParticipants: React.FC<PropsType> = ({
 
       let rowWidthSoFar = 0;
       return remoteParticipantsInRow.map(remoteParticipant => {
+        const { demuxId, videoAspectRatio } = remoteParticipant;
+
+        const isSpeaking = speakingDemuxIds.has(demuxId);
+
         const renderedWidth = Math.floor(
-          remoteParticipant.videoAspectRatio * gridParticipantHeight
+          videoAspectRatio * gridParticipantHeight
         );
         const left = rowWidthSoFar + leftOffset;
 
@@ -275,11 +281,12 @@ export const GroupCallRemoteParticipants: React.FC<PropsType> = ({
 
         return (
           <GroupCallRemoteParticipant
-            key={remoteParticipant.demuxId}
+            key={demuxId}
             getFrameBuffer={getFrameBuffer}
             getGroupCallVideoFrameSource={getGroupCallVideoFrameSource}
             height={gridParticipantHeight}
             i18n={i18n}
+            isSpeaking={isSpeaking}
             left={left}
             remoteParticipant={remoteParticipant}
             top={top}
@@ -411,6 +418,7 @@ export const GroupCallRemoteParticipants: React.FC<PropsType> = ({
             i18n={i18n}
             onParticipantVisibilityChanged={onParticipantVisibilityChanged}
             overflowedParticipants={overflowedParticipants}
+            speakingDemuxIds={speakingDemuxIds}
           />
         </div>
       )}

ts/components/Lottie.stories.tsx

@@ -0,0 +1,21 @@
+// Copyright 2022 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import React from 'react';
+import { storiesOf } from '@storybook/react';
+
+import { Lottie } from './Lottie';
+
+import testAnimationData from '../../fixtures/lottie-loader-by-lucas-bariani.json';
+
+const STORYBOOK_CONTAINER_CLASS_NAME = 'lottie-test-storybook-container';
+
+const story = storiesOf('Components/Lottie', module);
+
+story.add('Default', () => (
+  <Lottie
+    animationData={testAnimationData}
+    className={STORYBOOK_CONTAINER_CLASS_NAME}
+    style={{ width: 300, height: 300 }}
+  />
+));

ts/components/Lottie.tsx

@@ -0,0 +1,42 @@
+// Copyright 2022 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import type { CSSProperties, ReactElement } from 'react';
+import React, { useEffect, useRef } from 'react';
+import lottie from '@evanhahn/lottie-web-light';
+
+import { lottieNoopAudioFactory } from '../util/lottieNoopAudioFactory';
+
+export function Lottie({
+  animationData,
+  className,
+  style,
+}: Readonly<{
+  animationData: unknown;
+  className?: string;
+  style?: CSSProperties;
+}>): ReactElement {
+  const containerRef = useRef<null | HTMLDivElement>(null);
+
+  useEffect(() => {
+    const container = containerRef.current;
+    if (!container) {
+      return;
+    }
+
+    const animationItem = lottie.loadAnimation({
+      container,
+      renderer: 'svg',
+      loop: true,
+      autoplay: true,
+      animationData,
+      audioFactory: lottieNoopAudioFactory,
+    });
+
+    return () => {
+      animationItem.destroy();
+    };
+  }, [animationData]);
+
+  return <div className={className} ref={containerRef} style={style} />;
+}

ts/services/calling.ts

@@ -627,6 +627,7 @@ export class CallingClass {
       groupIdBuffer,
       this.sfuUrl,
       Buffer.alloc(0),
+      500,
       {
         onLocalDeviceStateChanged: groupCall => {
           const localDeviceState = groupCall.getLocalDeviceState();
@@ -674,8 +675,16 @@ export class CallingClass {
         onRemoteDeviceStatesChanged: groupCall => {
           this.syncGroupCallToRedux(conversationId, groupCall);
         },
-        onAudioLevels: _groupCall => {
-          // TODO: Implement audio level handling for group calls.
+        onAudioLevels: groupCall => {
+          const remoteDeviceStates = groupCall.getRemoteDeviceStates();
+          if (!remoteDeviceStates) {
+            return;
+          }
+
+          this.uxActions?.groupCallAudioLevelsChange({
+            conversationId,
+            remoteDeviceStates,
+          });
         },
         onPeekChanged: groupCall => {
           const localDeviceState = groupCall.getLocalDeviceState();
@@ -1955,6 +1964,8 @@ export class CallingClass {
       },
       hideIp: shouldRelayCalls || isContactUnknown,
       bandwidthMode: BandwidthMode.Normal,
+      // TODO: DESKTOP-3101
+      // audioLevelsIntervalMillis: 500,
     };
   }
 

ts/state/ducks/calling.ts

@@ -39,6 +39,7 @@ import type { UUIDStringType } from '../../types/UUID';
 import type { ConversationChangedActionType } from './conversations';
 import * as log from '../../logging/log';
 import { strictAssert } from '../../util/assert';
+import * as setUtil from '../../util/setUtil';
 
 // State
 
@@ -89,6 +90,7 @@ export type GroupCallStateType = {
   joinState: GroupCallJoinState;
   peekInfo: GroupCallPeekInfoType;
   remoteParticipants: Array<GroupCallParticipantInfoType>;
+  speakingDemuxIds?: Set<number>;
 } & GroupCallRingStateType;
 
 export type ActiveCallStateType = {
@@ -305,6 +307,7 @@ const CALL_STATE_CHANGE_FULFILLED = 'calling/CALL_STATE_CHANGE_FULFILLED';
 const CHANGE_IO_DEVICE_FULFILLED = 'calling/CHANGE_IO_DEVICE_FULFILLED';
 const CLOSE_NEED_PERMISSION_SCREEN = 'calling/CLOSE_NEED_PERMISSION_SCREEN';
 const DECLINE_DIRECT_CALL = 'calling/DECLINE_DIRECT_CALL';
+const GROUP_CALL_AUDIO_LEVELS_CHANGE = 'calling/GROUP_CALL_AUDIO_LEVELS_CHANGE';
 const GROUP_CALL_STATE_CHANGE = 'calling/GROUP_CALL_STATE_CHANGE';
 const HANG_UP = 'calling/HANG_UP';
 const INCOMING_DIRECT_CALL = 'calling/INCOMING_DIRECT_CALL';
@@ -370,6 +373,16 @@ type DeclineCallActionType = {
   payload: DeclineCallType;
 };
 
+type GroupCallAudioLevelsChangeActionPayloadType = Readonly<{
+  conversationId: string;
+  remoteDeviceStates: ReadonlyArray<{ audioLevel: number; demuxId: number }>;
+}>;
+
+type GroupCallAudioLevelsChangeActionType = {
+  type: 'calling/GROUP_CALL_AUDIO_LEVELS_CHANGE';
+  payload: GroupCallAudioLevelsChangeActionPayloadType;
+};
+
 export type GroupCallStateChangeActionType = {
   type: 'calling/GROUP_CALL_STATE_CHANGE';
   payload: GroupCallStateChangeActionPayloadType;
@@ -500,6 +513,7 @@ export type CallingActionType =
   | CloseNeedPermissionScreenActionType
   | ConversationChangedActionType
   | DeclineCallActionType
+  | GroupCallAudioLevelsChangeActionType
   | GroupCallStateChangeActionType
   | HangUpActionType
   | IncomingDirectCallActionType
@@ -706,6 +720,12 @@ function getPresentingSources(): ThunkAction<
   };
 }
 
+function groupCallAudioLevelsChange(
+  payload: GroupCallAudioLevelsChangeActionPayloadType
+): GroupCallAudioLevelsChangeActionType {
+  return { type: GROUP_CALL_AUDIO_LEVELS_CHANGE, payload };
+}
+
 function groupCallStateChange(
   payload: GroupCallStateChangeArgumentType
 ): ThunkAction<void, RootStateType, unknown, GroupCallStateChangeActionType> {
@@ -1242,6 +1262,7 @@ export const actions = {
   closeNeedPermissionScreen,
   declineCall,
   getPresentingSources,
+  groupCallAudioLevelsChange,
   groupCallStateChange,
   hangUp,
   hangUpActiveCall,
@@ -1631,6 +1652,40 @@ export function reducer(
     };
   }
 
+  if (action.type === GROUP_CALL_AUDIO_LEVELS_CHANGE) {
+    const { conversationId, remoteDeviceStates } = action.payload;
+
+    const existingCall = getGroupCall(conversationId, state);
+    if (!existingCall) {
+      return state;
+    }
+
+    const speakingDemuxIds = new Set<number>();
+    remoteDeviceStates.forEach(({ audioLevel, demuxId }) => {
+      // We expect `audioLevel` to be a number but have this check just in case.
+      if (typeof audioLevel === 'number' && audioLevel > 0.25) {
+        speakingDemuxIds.add(demuxId);
+      }
+    });
+
+    // This action is dispatched frequently. This equality check helps avoid re-renders.
+    const oldSpeakingDemuxIds = existingCall.speakingDemuxIds;
+    if (
+      oldSpeakingDemuxIds &&
+      setUtil.isEqual(oldSpeakingDemuxIds, speakingDemuxIds)
+    ) {
+      return state;
+    }
+
+    return {
+      ...state,
+      callsByConversation: {
+        ...callsByConversation,
+        [conversationId]: { ...existingCall, speakingDemuxIds },
+      },
+    };
+  }
+
   if (action.type === GROUP_CALL_STATE_CHANGE) {
     const {
       connectionState,

ts/state/smart/CallManager.tsx

@@ -1,4 +1,4 @@
-// Copyright 2020-2021 Signal Messenger, LLC
+// Copyright 2020-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import React from 'react';
@@ -251,6 +251,7 @@ const mapStateToActiveCallProp = (
         maxDevices: call.peekInfo.maxDevices,
         peekedParticipants,
         remoteParticipants,
+        speakingDemuxIds: call.speakingDemuxIds || new Set<number>(),
       };
     }
     default:

ts/test-both/util/iterables_test.ts

@@ -1,4 +1,4 @@
-// Copyright 2021 Signal Messenger, LLC
+// Copyright 2021-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import { assert } from 'chai';
@@ -6,6 +6,7 @@ import * as sinon from 'sinon';
 
 import {
   concat,
+  every,
   filter,
   find,
   groupBy,
@@ -170,6 +171,30 @@ describe('iterable utilities', () => {
     });
   });
 
+  describe('every', () => {
+    const isOdd = (n: number): boolean => Boolean(n % 2);
+
+    it('returns true for empty iterables and never checks the predicate', () => {
+      const fn = sinon.fake();
+
+      assert.isTrue(every([], fn));
+      assert.isTrue(every(new Set(), fn));
+      assert.isTrue(every(new Map(), fn));
+
+      sinon.assert.notCalled(fn);
+    });
+
+    it('returns false if any values make the predicate return false', () => {
+      assert.isFalse(every([2], isOdd));
+      assert.isFalse(every([1, 2, 3], isOdd));
+    });
+
+    it('returns true if all values make the predicate return true', () => {
+      assert.isTrue(every([1], isOdd));
+      assert.isTrue(every([1, 3, 5], isOdd));
+    });
+  });
+
   describe('filter', () => {
     it('returns an empty iterable when passed an empty iterable', () => {
       const fn = sinon.fake();

ts/test-both/util/setUtil_test.ts

@@ -1,13 +1,42 @@
-// Copyright 2021 Signal Messenger, LLC
+// Copyright 2021-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import { assert } from 'chai';
 
-import { remove, toggle } from '../../util/setUtil';
+import { isEqual, remove, toggle } from '../../util/setUtil';
 
 describe('set utilities', () => {
   const original = new Set([1, 2, 3]);
 
+  describe('isEqual', () => {
+    it('returns false if the sets are different', () => {
+      const sets = [
+        new Set([1, 2, 3]),
+        new Set([1, 2, 3, 4]),
+        new Set([1, 2]),
+        new Set([4, 5, 6]),
+      ];
+
+      for (const a of sets) {
+        for (const b of sets) {
+          if (a !== b) {
+            assert.isFalse(isEqual(a, b));
+          }
+        }
+      }
+    });
+
+    it('returns true if both arguments are the same set', () => {
+      const set = new Set([1, 2, 3]);
+      assert.isTrue(isEqual(set, set));
+    });
+
+    it('returns true if the sets have the same values', () => {
+      assert.isTrue(isEqual(new Set(), new Set()));
+      assert.isTrue(isEqual(new Set([1, 2]), new Set([2, 1])));
+    });
+  });
+
   describe('remove', () => {
     it('accepts zero arguments, returning a new set', () => {
       const result = remove(original);

ts/test-electron/state/ducks/calling_test.ts

@@ -776,6 +776,67 @@ describe('calling duck', () => {
       });
     });
 
+    describe('groupCallAudioLevelsChange', () => {
+      const { groupCallAudioLevelsChange } = actions;
+
+      const remoteDeviceStates = [
+        { audioLevel: 0.3, demuxId: 1 },
+        { audioLevel: 0.4, demuxId: 2 },
+        { audioLevel: 0.5, demuxId: 3 },
+        { audioLevel: 0.2, demuxId: 7 },
+        { audioLevel: 0.1, demuxId: 8 },
+        { audioLevel: 0, demuxId: 9 },
+      ];
+
+      it("does nothing if there's no relevant call", () => {
+        const action = groupCallAudioLevelsChange({
+          conversationId: 'garbage',
+          remoteDeviceStates,
+        });
+
+        const result = reducer(stateWithActiveGroupCall, action);
+
+        assert.strictEqual(result, stateWithActiveGroupCall);
+      });
+
+      it('does nothing if the state change would be a no-op', () => {
+        const state = {
+          ...stateWithActiveGroupCall,
+          callsByConversation: {
+            'fake-group-call-conversation-id': {
+              ...stateWithActiveGroupCall.callsByConversation[
+                'fake-group-call-conversation-id'
+              ],
+              speakingDemuxIds: new Set([3, 2, 1]),
+            },
+          },
+        };
+        const action = groupCallAudioLevelsChange({
+          conversationId: 'fake-group-call-conversation-id',
+          remoteDeviceStates,
+        });
+
+        const result = reducer(state, action);
+
+        assert.strictEqual(result, state);
+      });
+
+      it('updates the set of speaking participants', () => {
+        const action = groupCallAudioLevelsChange({
+          conversationId: 'fake-group-call-conversation-id',
+          remoteDeviceStates,
+        });
+        const result = reducer(stateWithActiveGroupCall, action);
+
+        const call =
+          result.callsByConversation['fake-group-call-conversation-id'];
+        if (call?.callMode !== CallMode.Group) {
+          throw new Error('Expected a group call to be found');
+        }
+        assert.deepStrictEqual(call.speakingDemuxIds, new Set([1, 2, 3]));
+      });
+    });
+
     describe('groupCallStateChange', () => {
       const { groupCallStateChange } = actions;
 

ts/types/Calling.ts

@@ -65,6 +65,7 @@ type ActiveGroupCallType = ActiveCallBaseType & {
   groupMembers: Array<Pick<ConversationType, 'id' | 'firstName' | 'title'>>;
   peekedParticipants: Array<ConversationType>;
   remoteParticipants: Array<GroupCallRemoteParticipantType>;
+  speakingDemuxIds: Set<number>;
 };
 
 export type ActiveCallType = ActiveDirectCallType | ActiveGroupCallType;

ts/util/iterables.ts

@@ -1,4 +1,4 @@
-// Copyright 2021 Signal Messenger, LLC
+// Copyright 2021-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 /* eslint-disable max-classes-per-file */
@@ -46,6 +46,18 @@ class ConcatIterable<T> implements Iterable<T> {
   }
 }
 
+export function every<T>(
+  iterable: Iterable<T>,
+  predicate: (value: T) => boolean
+): boolean {
+  for (const value of iterable) {
+    if (!predicate(value)) {
+      return false;
+    }
+  }
+  return true;
+}
+
 export function filter<T, S extends T>(
   iterable: Iterable<T>,
   predicate: (value: T) => value is S

ts/util/lint/exceptions.json

@@ -132,6 +132,41 @@
     "reasonCategory": "falseMatch",
     "updated": "2021-04-05T20:48:36.065Z"
   },
+  {
+    "rule": "jQuery-append(",
+    "path": "node_modules/@evanhahn/lottie-web-light/index.js",
+    "line": "      this._elementHelper.append(img);",
+    "reasonCategory": "falseMatch",
+    "updated": "2022-01-27T20:06:59.988Z"
+  },
+  {
+    "rule": "jQuery-insertBefore(",
+    "path": "node_modules/@evanhahn/lottie-web-light/index.js",
+    "line": "    this.layerElement.insertBefore(newElement, nextElement);",
+    "reasonCategory": "falseMatch",
+    "updated": "2022-01-27T20:06:59.988Z"
+  },
+  {
+    "rule": "jQuery-insertBefore(",
+    "path": "node_modules/@evanhahn/lottie-web-light/index.js",
+    "line": "    parentNode.insertBefore(useElem, nextChild);",
+    "reasonCategory": "falseMatch",
+    "updated": "2022-01-27T20:06:59.988Z"
+  },
+  {
+    "rule": "jQuery-load(",
+    "path": "node_modules/@evanhahn/lottie-web-light/index.js",
+    "line": "          _workerSelf.assetLoader.load(",
+    "reasonCategory": "falseMatch",
+    "updated": "2022-01-27T20:06:59.988Z"
+  },
+  {
+    "rule": "jQuery-load(",
+    "path": "node_modules/@evanhahn/lottie-web-light/index.js",
+    "line": "          _workerSelf.assetLoader.load(",
+    "reasonCategory": "falseMatch",
+    "updated": "2022-01-27T20:06:59.988Z"
+  },
   {
     "rule": "eval",
     "path": "node_modules/@protobufjs/inquire/index.js",
@@ -7494,6 +7529,14 @@
     "reasonCategory": "usageTrusted",
     "updated": "2021-10-11T21:21:08.188Z"
   },
+  {
+    "rule": "React-useRef",
+    "path": "ts/components/Lottie.tsx",
+    "line": "  const containerRef = useRef<null | HTMLDivElement>(null);",
+    "reasonCategory": "usageTrusted",
+    "updated": "2022-01-27T20:06:59.988Z",
+    "reasonDetail": "Doesn't manipulate the DOM."
+  },
   {
     "rule": "React-useRef",
     "path": "ts/components/Modal.tsx",

ts/util/lottieNoopAudioFactory.ts

@@ -0,0 +1,18 @@
+// Copyright 2022 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { noop } from 'lodash';
+import type { AnimationConfig } from '@evanhahn/lottie-web-light';
+
+type LottieAudioFactory = NonNullable<AnimationConfig['audioFactory']>;
+type LottieAudio = ReturnType<LottieAudioFactory>;
+
+const lottieNoopAudio: LottieAudio = {
+  play: noop,
+  seek: noop,
+  playing: noop,
+  rate: noop,
+  setVolume: noop,
+};
+
+export const lottieNoopAudioFactory: LottieAudioFactory = () => lottieNoopAudio;

ts/util/setUtil.ts

@@ -1,6 +1,8 @@
-// Copyright 2021 Signal Messenger, LLC
+// Copyright 2021-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
+import { every } from './iterables';
+
 const add = <T>(set: Readonly<Set<T>>, item: T): Set<T> =>
   new Set(set).add(item);
 
@@ -20,3 +22,8 @@ export const toggle = <T>(
   item: Readonly<T>,
   shouldInclude: boolean
 ): Set<T> => (shouldInclude ? add : remove)(set, item);
+
+export const isEqual = (
+  a: Readonly<Set<unknown>>,
+  b: Readonly<Set<unknown>>
+): boolean => a === b || (a.size === b.size && every(a, item => b.has(item)));